1. Field of the Invention
The invention relates to the field of valves. In particular the invention relates to check valves that reduce leakage caused by flapping.
2. Description of the Related Technology
The main cause of returned balloon products is because of leaky valves. A number of check valves exist for balloons for permitting the entrance of fluids, such as gasses or water, but not permitting the fluids to then escape from the balloon once the fluid has entered the balloon. A problem with existing valves is that during the inflation process the valve flaps back and forth. When the valve flaps it causes a slight over pressure in the outlet section of the valve. This causes the plastic to stretch and the valve to leak.
FIGS. 1 and 2 show a conventional balloon valve 10. FIG. 1 shows self-sealing valve 10 as placed within non-latex balloon 12. As is well known in the art, balloon 12 includes a body 14 and a stem 16, defined by two flexible plastic balloon sheets 18, 20 that are constructed with a heat-sealable material. Body 14 of balloon 12 is inflatable with an inflation fluid, such as air or helium, through stem 16. Stem 16 extends from a boundary 34, shown as a dashed line in FIG. 1 and extends to the distal end 22.
As shown in FIG. 2, valve 10 is constructed of first and second flexible plastic valve sheets that are sealed or fused along two longitudinal edge lines 50, 52. The first and second sheets have a thickness in the range of 1 to 3 mm. After the sheets are sealed together, the first and second valve sheets cooperate to define a valve inlet 64, valve outlet 66 and valve passageway 68 extending there between. The valve passageway 68 includes an inlet section 70 extending from the valve inlet 64, an outlet section 72 extending from the valve outlet 66, and an interconnecting offset section 74. As shown, the outlet section 72 has a width corresponding to the width of the valve outlet 66, and the inlet section 70 has greater width corresponding to that of the valve inlet 64. The offset section 74 provides a relatively smooth transition between the inlet and outlet sections 70, 72 and defines an offset angle, designated “A” on FIG. 2, in the range of fifteen to forty degrees.
As shown in FIG. 1, valve 10 lies entirely within the balloon 12. That is, a first portion 80 of valve 10 extends into the body 14 and is substantially free or floating. This floating first portion 80 facilitates sealing under pressure in that the floating first portion 80 often partially folds over to crease the valve passageway 68. A second portion 82 of valve 10 extends beyond the boundary 34 and partially into the stem 16. This second portion 82 includes valve inlet 64 and is bonded to the balloon stem 16 in the final assembled balloon state. The second portion 82 of the valve 10 is heat-sealed to the balloon sheets 18, 20.
The outlet section 72, formed by the heat-seal along the parallel edge lines 50 and 52 causes valve 10 to flap back and forth during inflation. When the valve flaps it causes a slight over pressure in the outlet section 72 of valve 10. This causes the plastic to stretch and valve 10 to leak. Utilization of higher-pressure inflators increases the chances that a leak will occur.
Changing the way valve 10 is shaped and heat-sealed will produce a stronger valve that reduces flapping. By reducing flapping, higher pressure inflators can be used which can reduce the overall amount of labor time needed to inflate the balloons and also reduce the loss of product caused by leaky valves.
Therefore, a need exists to produce a valve that reduces overall leakage caused by flapping and therefore reduces the loss of product due to leakage and permits the usage of higher-pressure inflators.